Purpose: Sabatolimab (MBG453) and spartalizumab are mAbs that bind T-cell immunoglobulin domain and mucin domain-3 (TIM-3) and programmed death-1 (PD-1), respectively. This phase I/II study... Show morePurpose: Sabatolimab (MBG453) and spartalizumab are mAbs that bind T-cell immunoglobulin domain and mucin domain-3 (TIM-3) and programmed death-1 (PD-1), respectively. This phase I/II study evaluated the safety and efficacy of sabatolimab, with or without spartalizumab, in patients with advanced solid tumors.Patients and Methods: Primary objectives of the phase I/Ib part were to characterize the safety and estimate recommended phase II dose (RP2D) for future studies. Dose escalation was guided by a Bayesian (hierarchical) logistic regression model. Sabatolimab was administered intravenously, 20 to 1,200 mg, every 2 or 4 weeks (Q2W or Q4W). Spartalizumab was administered intravenously, 80 to 400 mg, Q2W or Q4W.Results: Enrolled patients (n = 219) had a range of cancers, most commonly ovarian (17%) and colorectal cancer (7%); patients received sabatolimab (n = 133) or sabatolimab plus spartalizumab (n = 86). The MTD was not reached. The most common adverse event suspected to be treatment-related was fatigue (9%, sabatolimab; 15%, combination). No responses were seen with sabatolimab. Five patients receiving combination treatment had partial responses (6%; lasting 12-27 months) in colorectal cancer (n = 2), non-small cell lung cancer (NSCLC), malignant perianal melanoma, and SCLC. Of the five, two patients had elevated expression of immune markers in baseline biopsies; another three had >10% TIM-3-positive staining, including one patient with NSCLC who received prior PD-1 therapy.Conclusions: Sabatolimab plus spartalizumab was well tolerated and showed preliminary signs of antitumor activity. The RP2D for sabatolimab was selected as 800 mg Q4W (alternatively Q3W or Q2W schedules, based on modeling), with or without 400 mg spartalizumab Q4W. Show less
BackgroundSpartalizumab is a humanized IgG4 kappa monoclonal antibody that binds programmed death-1 (PD-1) and blocks its interaction with PD-L1 and PD-L2. This phase 1/2 study was designed to... Show moreBackgroundSpartalizumab is a humanized IgG4 kappa monoclonal antibody that binds programmed death-1 (PD-1) and blocks its interaction with PD-L1 and PD-L2. This phase 1/2 study was designed to assess the safety, pharmacokinetics, and preliminary efficacy of spartalizumab in patients with advanced or metastatic solid tumors.MethodsIn the phase 1 part of the study, 58 patients received spartalizumab, intravenously, at doses of 1, 3, or 10 mg/kg, administered every 2 weeks (Q2W), or 3 or 5 mg/kg every 4 weeks (Q4W).ResultsPatients had a wide range of tumor types, most commonly sarcoma (28%) and metastatic renal cell carcinoma (10%); other tumor types were reported in <= 3 patients each. Most patients (93%) had received prior antineoplastic therapy (median three prior lines) and two-thirds of the population had tumor biopsies negative for PD-L1 expression at baseline. The maximum tolerated dose was not reached. The recommended phase 2 doses were selected as 400 mg Q4W or 300 mg Q3W. No dose-limiting toxicities were observed, and adverse events included those typical of other PD-1 antibodies. The most common treatment-related adverse events of any grade were fatigue (22%), diarrhea (17%), pruritus (14%), hypothyroidism (10%), and nausea (10%). Partial responses occurred in two patients (response rate 3.4%); one with atypical carcinoid tumor of the lung and one with anal cancer. Paired tumor biopsies from patients taken at baseline and on treatment suggested an on-treatment increase in CD8+ lymphocyte infiltration in patients with clinical benefit.ConclusionsSpartalizumab was well tolerated at all doses tested in patients with previously treated advanced solid tumors. On-treatment immune activation was seen in tumor biopsies; however, limited clinical activity was reported in this heavily pretreated, heterogeneous population. The phase 2 part of this study is ongoing in select tumor types. Show less
